GARDASIL

Gardasil

Gardasil

Introduction

Genital human papillomavirus (HPV) is the most common sexually transmitted infection, accounting for an estimated 6.2 million new infections in the United States annually.1 Over 40 identified types of HPV have been linked to genital warts and cervical cancer. and Cervical cancer is the second most common female cancer in the world, resulting in over a quarter of a million deaths worldwide every year(Alferivic, 2004, pp.1849-53).

Human papillomaviruses (HPV) are highly prevalent DNA viruses that infect epithelial cells. Persistent viral infection with oncogenic types of ,HPV leads to cancer of the cervix, anus, vagina, bulva, penis, moth, and sinuses. Cervical cancer is the second most common malignant disease reported in women worldwide.

Use of the Pap smear has significantly reduced the incidence and mortality of cervical cancer in women who have regular screening and follow-up.5 However, the test has been inadequate in universally preventing cervical cancer. Pap smear sensitivity is poor, ranging from 50% to 74%, depending on the methodology.6 In addition, the test is not sufficiently used. An analysis of the 1998 National Health Interview Survey by the Centers for Disease Control and Prevention of more than 100,000 individuals revealed that only 83% of women aged 40 to 64 years reported Pap testing in the previous 3 years.7 Screening rates are lower among women who are uninsured, younger, poorer, and less educated, and likely contributing to the higher cervical cancer mortality in minority groups such as African Americans.9 Even among women who have screening, approximately 40% with abnormal Pap smear results fail to return for additional testing.10 Routine Pap testing is also problematic in developing countries where there are often limited resources for technology, laboratories, and screening programs.11 These challenges suggest a preventative strategy may be more effective in reducing precancerous lesions and cervical cancer.

One potential approach is the use of the quadrivalent HPV vaccine, which was approved by the Food and Drug Administration in June 2006. Several clinical studies have demonstrated vaccine efficacy in protecting against infection with the four HPV types associated with approximately 70% of all cervical cancer cases and more than 90% of genital warts. The vaccine has the potential to significantly reduce morbidity and mortality associated with cervical disease(Sakai , 2006, pp.14-19).

Gardasil protects against 2 strains of HPV, 16 and 18, that are responsible for about 70% of all cervical cancers and most vaginal and vulvar cancers. It also protects against 2 other HPV strains that cause about 90% of cases of genital warts. HPV is a very common sexually transmitted virus. Most people who have ever had sex, both men and women, have been infected at some point in their lives. Most people never even know they've had HPV because the virus usually doesn't cause any symptoms and the body is able to fight it off easily. Sometimes, though, the virus doesn't go away. If the virus lingers in a woman's cervix, it can cause changes that may eventually lead to cervical cancer. In clinical trials involving 21,000 women and teenage girls, the vaccine was ...